The Rockbridge plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
79° on Nov. 11, 2020, the hottest reading for this week of the year since 1896. Next is 75° in 2002.
Rockbridge’s center stands about 840 ft above sea level. Within three miles the land runs from 750 ft to 1,110 ft, a difference of 360 ft: rolling country. The highest named summit within 15 miles is Jacobs Ladder, about 1,250 ft, 8 miles northwest.
Under the town center the state geologic map shows Black Hand Sandstone Member of Cuyahoga Formation (sandstone, conglomerate), from the Carboniferous, 324 to 359 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 38×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, conglomerate. Age: Carboniferous, 324 to 359 million years old. About 15 mi of the line.
Shale, siltstone. Age: Carboniferous, 299 to 324 million years old. About 7 mi of the line.
Shale, siltstone, sandstone. Age: Devonian to Carboniferous, 324 to 422 million years old. About 3 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in Rockbridge reaches the Gulf of America by way of the Hocking, the Ohio and the Mississippi: about 1,820 river miles.
970 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Rockbridge; river miles along the main stem, rounded.
Rockbridge has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 19° in January. About 43 inches of rain fall in a normal year.
Normals 1991–2020 and records since 1896 at Logan, 8 miles east-southeast, 120 ft lower. NOAA, through RCC-ACIS.